To examine the association between interferon beta exposure and disability progression in patients with relapsing-remitting multiple sclerosis, Shirani and colleagues analyzed data from the British Columbia Multiple Sclerosis Database. Disability progression in 3 cohorts of patients was compared: 868 patients treated with interferon beta, 829 untreated contemporary control patients, and 959 historical (untreated) control patients. The authors report that administration of interferon beta was not associated with a significant reduction in the progression of disability. In an editorial, Derfuss and Kappos discuss interferon treatment in multiple sclerosis.

Fonarow and colleagues analyzed data from 127 950 Medicare beneficiaries with ischemic stroke who were treated at 782 hospitals participating in the Get With The Guidelines–Stroke quality improvement program to compare hospital performance based on 30-day hospital mortality risk models with vs without adjustment for initial stroke severity. The authors found that inclusion of initial stroke severity in the risk models was associated with improved prediction of 30-day mortality and changed mortality performance rankings for a substantial proportion of hospitals. In an editorial, Kurth and Elkind discuss the need to consider stroke severity when comparing hospitals' stroke care outcomes.

In an analysis of administrative data from more than 4.5 million Medicare beneficiaries seen by 68 288 physicians practicing in 51 nationally representative hospital referral regions, Landon and colleagues defined informal social networks of physicians who shared patients, examined geographic variation in the networks, and identified physician and patient factors associated with patient-sharing relationships. Among the authors' findings were that physicians with network connections were more likely to be in close geographic proximity and to have more similar patient panels (eg, race, illness burden) than unconnected physicians. In an editorial, Lewis and Fisher discuss the importance of understanding social networks in health care.

Silymarin—an extract of milk thistle—is a commonly used botanical among patients with liver disease. Some in vitro data suggest that silymarin has anti-inflammatory and immunomodulatory properties and may affect hepatitis C virus replication. In a 24-week randomized, placebo-controlled trial involving 154 patients with chronic hepatitis C unsuccessfully treated with interferon-based therapy, Fried and colleagues found that silymarin at higher than customary doses—either 420 mg or 700 mg, 3 times a day—did not improve serum alanine aminotransferase levels compared with placebo.

A 62-year-old man with a history of alcohol abuse, several weeks' nonproductive cough, weight loss, and bilateral infiltrates on chest radiograph was hospitalized with a presumptive diagnosis of pneumonia. A sputum sample was positive for rare acid-fast bacilli. Gordin and Masur discuss current approaches to the diagnosis and treatment of tuberculosis (TB) in the United States.